Durable press resins, also known as "aminoplast resins", have been described in U.S. Pat. No. 4,300,898 to North, for treating textile materials to impart durable press properties and dimensional stability to treated textile materials. These durable press resins, such as methylolated ureas or methylolated urea based derivatives which are obtained from the reaction of formaldehyde and urea or urea based derivatives generally contain 2.2 to 4.2 weight percent of formaldehyde.
Textile materials treated with the durable press resins generally release formaldehyde either present in the durable press resin and/or through the hydrolysis of unreacted methylol groups. The formaldehyde causes unpleasant odors and is a suspected health hazard. Therefore, it is preferred that textile materials finished with durable press resins be free of formaldehyde or at least have very low levels of formaldehyde and have as few as possible unreacted methylol groups.
In order to reduce the formaldehyde level on treated fabrics, scavengers such as cyclic ethylene urea, propylene urea and certain nitrogen-containing heterocyclic compounds have been employed. Also, U.S. Pat. No. 3,723,058 discloses reacting formaldehyde with phthalimide to remove the formaldehyde.
Another possible method of reducing the formaldehyde level is to apply a conventional aminoplast resin to textile materials at low levels; however, it does not give satisfactory durable press properties.
Surprisingly, it has been found that satisfactory durable press properties may be achieved if an aldehyde is added to a low level of aminoplast resin. Moreover, it has been found that the addition of the aldehyde does not substantially increase the amount of free formaldehyde on the textile materials. In addition, durable press properties can be achieved at lower costs and with less potential toxicological problems in the work environment as well as for the consumer.
Therefore, it is an object of the present invention to provide textile finishing compositions for treating textile materials. Another object of this invention is to provide textile finishing compositions which impart softening and durable press properties to textile materials. A further object of this invention is to provide a textile material having low formaldehyde levels, a soft hand, durable press properties and dimensional stability characteristics.